I live in CT and hike here a lot. It's great here in late April. Early to mid-May is when the trees tend to leaf out. It's a beautiful time of year, with tons of sun. As noted, can be pretty cold some nights, with the occasional excursion into the 80s days, even 90s, rarely.
The proscription on VT mud season hiking certainly applies, though the problem is the place is called "Vermud" for a reason. It's muddy there most of the time when it's not frozen, at least on large portions of the year. My first VT hike, of Stratton on October 9, 2010, I ran into numerous mud pits, and not all up above 3K elevation.
My second Stratton hike was May 19, 2012, a relatively dry year, and it was not muddy at all in what normally is the height of mud season. Gotta monitor trail condition reports such as at newenglandtrailconditions.com (which I had done for that May hike, so I knew mud wouldn't be an issue). Sorry if that link is a duplicate - I didn't read through the entire thread closely.
I say go for it - unless it's an unusually bad year, Spring hiking 150 miles either side of the CT/NY border is good going - a beautiful time of year.